Towing Safety

About to buy your first trailer-towing vehicle? Here’s a system for making sure you get what you need. For additional information, AAAhas a great website detailing driving laws in every state pertaining to trailer brakes, trailer dimensions, trailer hitches, trailer lights, trailer mirrors, trailer speeds, towing and more atdrivinglaws.aaa.com

(AS SEEN IN HORSE & RIDER MAGAZINE)

RULES OF THE ROAD

Rule 1: Don’t under buy! According to my sources, one of the biggest mistakes you can make is to put gas mileage ahead of available power on your priority list. (As one person put it, “The first time your higher-mileage rig ‘dies’ on a steep hill, leaving you to unload and walk your horses to the top, those extra few miles per gallon won’t mean a thing.”) While a less powerful vehicle may also have a lower sticker price than one with a “workhorse” engine, repair bills or accidents can be your unhappy payback – and you’ll really be unhappy if you’re back at the dealership six months after buying a vehicle that just can’t do the job.

Rule 2: Get an automatic transmission, not a manual one. You’ll run less risk of overworking the transmissions thereby reducing the chance of a breakdown – and your horses will appreciate the smoother ride. Plus, without having to operate a gear shift and clutch, you’ll have that much more attention to to road conditions, and the way your horses are riding.

(You may disagree if you’re someone who’s comfortable with a manual transmission, believing you get better control when you can shift gears as needed. Nevertheless the experts I consulted all agreed that in general, an automatic transmission will have a longer lifetime than a manual one when used for towing, because the clutch in a manual transmissions may need frequent replacement with this kind of workload. It’s also a fact that a vehicle with an automatic transmission will have a slightly higher tow rating than one with the same-sized engine and a manual transmission – again, primarily because of the clutch.)

Rule 3: Insist on good tires, ones capable of handling the load you’ll be hauling. How can you tell? Simple – to haul two or three horses, specify 6-ply radials, load range C. These tires actually can handle a loaded tow weight of up to 10,000 pounds, the equivalent of a fully loaded four-horse trailer (though for a load this heavy, you might want to move up to 8-ply load range D). You may have heard that bias tires, with their stiff sidewalls, are better than radials for towing. That used to be true, but no more. Radials now are manufactured with stronger, stiffer sidewalls than in years past, and as a result, they’ve taken over the marketplace.

Rule 4: If a “tow package” is offered as an option for any vehicle you buy, say yes, What exactly is a tow package? Usually, this term refers to a group of manufacturer’s options that’ll help you tow your load; these options may include transmission – and engine – oil cooling systems (to prolong the life of these parts); heavy-duty suspension (to produce a firm, non-bouncy ride for you and your horses alike); heavy-duty wiring harness (for an easy, more reliable hookup to the trailer’s electrical system); and a more favorable “axle ratio.” (I’ll explain axle ratios when I talk about your engine’s pulling power.)

HAUL MONITORS

By now, you may have a vision of the towing rig you’d like, but don’t trot off to wheel and deal just yet – we still need to go over construction factors that determine whether a particular vehicle can safely and effectively tow your load.

Loaded tow weight: This is the weight of your trailer, plus the weight of your horses, feed, and gear. The greater the loaded tow weight, the more strain your towing vehicle must endure, and the bigger, and better-equipped vehicle you must have if you’re to haul without accident or breakdown. (This is just one reason for the rising popularity of aluminum horse trailers – they weigh far less than their steel counterparts, and therefore don’t require as ‘macho’ a towing vehicle.)

The most accurate – and recommended – way to determine your loaded tow weight is to take your fully loaded trailer, horses, hay and all, to a public scale to be weighed. That advice isn’t much help, though, when you don’t have a towing vehicle to start with, and may not yet have purchased a trailer! Therefore, we’ve estimated loaded tow weights (LTW) for you. Find the best match for your circumstances.

Tow rating

In theory, you should be able to match your loaded tow weight to the tow rating quoted in a vehicle’s product literature, and be all set. The matter isn’t that simple, however, and here’s why.

First of all, depending on how it’s equipped, a single model can have as many as a dozen tow ratings; my sources say this is especially true of trucks. Not only that, but tow ratings are calculated on the assumption that the towing vehicle itself won’t be heavily loaded – yet when the towing vehicle is heavily loaded, the tow rating goes down accordingly.

This business about tow rating is just one reason why I urge you to take your spec sheet with you when you go shopping. More importantly, don’t take the salesman’s word on tow rating. Instead, contact manufacturers to obtain the detailed tow-rating information on vehicles that interest you. It’s quite likely that you’ll have to order a vehicle to get what you truly need anyway, so this relatively brief delay in your future as an independent horse hauler won’t be that great in the overall scheme of things.

Vehicle weights

This term refers to the weight of the towing vehicle itself. Vehicle weight is one of several factors that affect the stability of your overall haling rig. Ideally, vehicle weight should match or exceed your loaded tow weight; that way, the loaded trailer doesn’t end up being the tail that wags the dog. (If you were to pair a light towing vehicle with a substantially heavier towed load, you’d find it difficult to steer and stop. Downhill travel would be especially dangerous – the trailer could sway out of control, pulling your entire rig off the road.)

Though a match of vehicle weight to loaded two weight is ideal, it’s not always possible (just imagine the 10,000-pound monstermobile it’d take to tow 10,000 pounds) – nor is it necessary. Provided your towing rigs engine size, wheelbase, and axle ratio are adequate (more on those coming up), you’ll be road-safe with a vehicle weight that’s three-quarters of your loaded tow weight. On your spec sheet, you should use one of the following:

Wheelbase

As I stated earlier, a towing vehicle’s wheelbase is the distance measured from front to rear axle. The longer the wheelbases, the greater your vehicle’s ability to hug the road, hence, the safer it is to tow with. The minimum safe wheelbase for pulling a standard (no dressing room), fully loaded two-horse with a frame-mounted hitch is 114 inches. That fact alone automatically disqualifies some vehicles from consideration as safe horse-hauling rigs – and don’t let anyone tell you otherwise! You’ll be hauling live cargo, not a load-stable boat or other item, and thus will need all the stability you can get. (As a veterinarian, I’ve tended more than my share of trailer-wreck victims – and I don’t want to meet you under those circumstances.) Here’s the info for your spec sheet:

Engine size

The engine size and number of cylinders tell you how much power a vehicle can produce. Engine size may be expressed either in cubic inches (for example, 350 or 460), but these days, it’s more common for size to be expressed in liters (for example,. 5.7 or 7.5). Don’t consider any vehicle with just four cylinders for horse hauling. You’ll need either six or eight. (To safely tow two horses, you’ll need at least a six-cylinder, 4.9 liter engine.)

Choose the specification that fits your situation, and if you can possibly afford it, plan to buy larger. (Tip: If you plan to tow horses in the mountains, you’ll definitely need to get an engine larger than the sizes quoted. Most engines lose 4 percent of their sea-level performance for every 1,000 feet of altitude. So, at 5,000 feet, for example, you’ll experience a 20 percent drop in power.)

Gear-axle ratio

This refers to the relationship between how hard (or “fast”) the engine is running, and how fast the axles (and therefore the wheels) are turning. The more powerful the engine and the higher the axle-ration number, the more acceleration you’ll have when you start out, pass, or climb a grade. Most vehicles with a high tow rating have an axle-ratio number in the 3.5:1 to 4.5:1 range. In practical terms, a vehicle with a six-cylinder engine with a higher-numbered axle ratio can tow the same load as a rig with an eight-cylinder engine. Spec the following: